BACKGROUND - The relation among acne vulgaris, foods and treatment with essential fatty acids is unknown; however essential fatty acids are important in the pathophysiology of acne vulgaris.

OBJECTIVES - To verify the clinical response of acne vulgaris with essential fatty acids and to establish the best methods to assess therapy.

METHODS - Thirty-one volunteers took part in the study; in that, 16 (51.6%) received a product rich in essential fatty acids and 15 (48.4%) received a placebo. Clinical examination, volunteer's self-evaluation (subjective score), digital image and pathological evaluation were performed before and after treatment.

RESULTS - There was no difference in the subjective score (p=0.419) and digital analysis (p=0.2187) between the product and placebo groups; there was a suggestive sign of improvement based on the pathological examination (p=0.087) but the chi-squared test showed no significance (¯2= 4.878); there was no statistical correlation between digital analysis and subjective score (p=0.127), between the subjective score and pathological examination (p=0.438). However, pathological and digital analyses showed correlation (p=0.012).